In October 2006, US secretary of state Condoleezza Rice urged prime minister Ehud Olmert to free imprisoned terrorist Marwan Barghouti. Her naÃ¯ve argument was that the Tanzim leader remained very popular among Palestinians, and that he was likely the only Fatah representative who could successfully advance the US-led "Middle East peace process." Today, not without irony, similar arguments are being raised in Israel itself, even in the Knesset. Following the election of Barghouti to Fatah's powerful central committee last week, Minority Affairs Minister Avishay Braverman (Labor) said: "In light of the election results, we must consider releasing him in order to create a moderate and strong political leadership among the Palestinians." At face value, Braverman's argument is also naÃ¯ve and flawed. But the overall case against freeing this terrorist must now be understood not only from the standpoint of geopolitics, but also in terms of binding international law. Not only is Braverman ignoring that a Barghouti release could elicit new terror attacks, upon Israelis, he also overlooks the fact that "pragmatic" release would violate basic and indispensable principles of law and justice. "No crime without a punishment." Codified in multiple sources after the Nuremberg Trials, this principle (called a peremptory in jurisprudence) is so rudimentary under international law that it can "never be disregarded." Indeed, apart from formal legal considerations, even simple decency and common morality dictate that a state should not trade away justice in exchange for presumed and momentary diplomatic expedience. Let us also not forget that Barghouti's great popularity among Palestinians remains rooted in his "operational specialty." This was the willful murder of Jews in Israel. WHEN THE victorious allied powers established a military tribunal at Nuremberg on August 8, 1945, they reaffirmed an ancient principle of law: Criminals, especially those who had committed crimes of war, crimes against peace and crimes against humanity, will be punished. In 1946, this reaffirmation was incorporated in Principle I of the Nuremberg Principles: "Any person who commits an act which constitutes a crime under international law is responsible therefore and liable to punishment." These principles, further formulated by the United Nations International Law Commission in 1950, stipulate: "Offenses against the peace and security of mankind... are crimes under international law, for which all responsible individuals shall be punished." In law, terrorism is a codified offense (a "grave breach") against the "peace and security of mankind." Marwan Barghouti was openly responsible for dozens of suicide bomb attacks on civilians and was - until his capture, trial and imprisonment - one of the world's most wanted criminals. He was arrested by Israeli special forces on April 15, 2002, and then brought to trial. The imprisonment of Barghouti serves far more than Israel's national interest. It also represents vital support for our largely self-help system of international law. Even today, when there exists an International Criminal Court, this largely volitional or cooperative system must rely upon the steady willingness of individual states to use their own domestic courts for the prosecution of terrorists. In its trial of Barghouti, Israel thus acted correctly on behalf of the entire international community. By contemporary international law standards, these terrorists are known as "common enemies of humankind." In the fashion of pirates, who were to be hanged by the first proper authorities into whose hands they fell, these wrongdoers are international outlaws who come fully within the scope of "universal jurisdiction." Punishment of violent crime must lie at the heart of justice. IN OUR sovereignty-centered system of world law, prosecution by individual states is still generally the only available path to punishment. In the absence of Israel's essential and law-enforcing operations against Palestinian terrorism, outlaws like Barghouti would remain free to commit further crimes. Immune to the legal expectations of extradition and prosecution (the Palestinian Authority has never complied with these obligations of international criminal law, not under Oslo and not under the road map), Barghouti would have proceeded contentedly with his organization of Palestinian children into explosive cadres of "martyrs." Naturally, he has never had any corollary intentions to explode himself. Barghouti, of course, thinks of himself as a heroic "liberator." But even if his declared objective of Palestinian self-determination could be accepted under authoritative international law, the particularly violent means he chose were indisputably unlawful. The Law of Armed Conflict, which applies to insurgents as well as to uniformed armies, makes it clear that the ends can never justify the means. No cause, even if it is presumed legitimate, can ever excuse the deliberate use of violence against the innocent. All of Israel's past actions in the Barghouti case, custodial and juridical, are supported by American law. For the US, the Nuremberg obligation to punish terrorists is doubly binding. This obligation represents not only basic rules under international law, but also the call of a higher law that is embedded in the American system. All international criminal law is part of the law of the United States, an incorporation expressed in Article VI of the US Constitution, and in associated Supreme Court decisions. On September 12, 2001, when Israeli flags were all lowered to half staff to honor America's most recent fallen, Marwan Barghouti enthusiastically celebrated America's national misfortune. This Palestinian terrorist leader whom some Israelis seek to restore to political authority and power is a sworn enemy of the United States. It is improper and imprudent, therefore, that anyone in Israel, least of all any member of Knesset, now call for this terrorist's release. The writer is the author of many books and articles dealing with international criminal law.